Camaro Cage

[Bill71]

I am having a roll cage installed in my 1971 Camaro in the next few weeks. I am setting up the car for NASA HPDE track outings. I spoke with the shop that will be doing the work and they said to get 360 degree welds on the main hoop will require cutting holes in the floor, welding the forward bars and then raising the hoop and plating the floor under the bar. I took a picture of where I will want the bar located and I believe it is a critical structure area of the car. Will anything be compromised if I let them go ahead and cut through the floor? Is there anything I should request as far as reinforcements? Here is a pic of the area in question.